Q: My car instantly overheats

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I've been having issues with my car's cooling system since late May and it's only gotten worse. I've taken it to a shop and they didn't find anything wrong with it, and after burping it today and shaking it back and forth it started overheating after only a few blocks. The heater stipped working as well and only cold air comes out of it but it doesn't smell like coolant. I checked the bottom hose on the radiator and it was cold, as was the radiator itself so it seems something went out or a blockage has occured. What do the symptoms point to and how can I diagnose it?

My car has 142000 miles.
My car has an automatic transmission.

Hello. This is a common issue when the thermostat is failing. This may also be caused when the coolant fan relays are not working properly. If the thermostat is stuck closed, this may cause the coolant to not circulate properly which will of course cause the car to overheat. I would recommend having an expert from YourMechanic come to your home to diagnose your car’s overheating problem and repair or replace the thermostat if necessary.

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